US20180229394A1 - Structural butt finger joint for flat boards - Google Patents
Structural butt finger joint for flat boards Download PDFInfo
- Publication number
- US20180229394A1 US20180229394A1 US15/537,000 US201515537000A US2018229394A1 US 20180229394 A1 US20180229394 A1 US 20180229394A1 US 201515537000 A US201515537000 A US 201515537000A US 2018229394 A1 US2018229394 A1 US 2018229394A1
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- United States
- Prior art keywords
- finger
- board
- profile
- finger profile
- boards
- Prior art date
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- 210000001145 finger joint Anatomy 0.000 title claims description 24
- 230000008878 coupling Effects 0.000 claims abstract description 8
- 238000010168 coupling process Methods 0.000 claims abstract description 8
- 238000005859 coupling reaction Methods 0.000 claims abstract description 8
- 238000000034 method Methods 0.000 claims description 21
- 238000003801 milling Methods 0.000 claims description 19
- 239000000853 adhesive Substances 0.000 claims description 16
- 230000001070 adhesive effect Effects 0.000 claims description 16
- 239000003292 glue Substances 0.000 claims description 14
- 239000000463 material Substances 0.000 claims description 13
- 239000011347 resin Substances 0.000 claims description 12
- 229920005989 resin Polymers 0.000 claims description 12
- 230000000295 complement effect Effects 0.000 claims description 10
- 238000010276 construction Methods 0.000 claims description 9
- 239000002023 wood Substances 0.000 claims description 9
- 238000004026 adhesive bonding Methods 0.000 claims description 7
- 210000001503 joint Anatomy 0.000 claims description 7
- 238000005094 computer simulation Methods 0.000 claims description 6
- 230000001154 acute effect Effects 0.000 claims description 5
- 239000012615 aggregate Substances 0.000 claims description 2
- 239000000835 fiber Substances 0.000 claims description 2
- 239000007769 metal material Substances 0.000 claims description 2
- 238000000465 moulding Methods 0.000 claims description 2
- 239000011120 plywood Substances 0.000 claims description 2
- 239000000843 powder Substances 0.000 claims description 2
- 239000003153 chemical reaction reagent Substances 0.000 claims 1
- 230000001681 protective effect Effects 0.000 claims 1
- 230000005540 biological transmission Effects 0.000 abstract description 4
- 238000004519 manufacturing process Methods 0.000 description 3
- 230000007812 deficiency Effects 0.000 description 2
- 241000761557 Lamina Species 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 238000005253 cladding Methods 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 230000001143 conditioned effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000011065 in-situ storage Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 238000009966 trimming Methods 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27F—DOVETAILED WORK; TENONS; SLOTTING MACHINES FOR WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES
- B27F1/00—Dovetailed work; Tenons; Making tongues or grooves; Groove- and- tongue jointed work; Finger- joints
- B27F1/16—Making finger joints, i.e. joints having tapers in the opposite direction to those of dovetail joints
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27C—PLANING, DRILLING, MILLING, TURNING OR UNIVERSAL MACHINES FOR WOOD OR SIMILAR MATERIAL
- B27C5/00—Machines designed for producing special profiles or shaped work, e.g. by rotary cutters; Equipment therefor
- B27C5/10—Portable hand-operated wood-milling machines; Routers
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27D—WORKING VENEER OR PLYWOOD
- B27D1/00—Joining wood veneer with any material; Forming articles thereby; Preparatory processing of surfaces to be joined, e.g. scoring
- B27D1/10—Butting blanks of veneer; Joining same along edges; Preparatory processing of edges, e.g. cutting
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27F—DOVETAILED WORK; TENONS; SLOTTING MACHINES FOR WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES
- B27F1/00—Dovetailed work; Tenons; Making tongues or grooves; Groove- and- tongue jointed work; Finger- joints
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27M—WORKING OF WOOD NOT PROVIDED FOR IN SUBCLASSES B27B - B27L; MANUFACTURE OF SPECIFIC WOODEN ARTICLES
- B27M3/00—Manufacture or reconditioning of specific semi-finished or finished articles
- B27M3/0013—Manufacture or reconditioning of specific semi-finished or finished articles of composite or compound articles
- B27M3/002—Manufacture or reconditioning of specific semi-finished or finished articles of composite or compound articles characterised by oblong elements connected at their ends
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27M—WORKING OF WOOD NOT PROVIDED FOR IN SUBCLASSES B27B - B27L; MANUFACTURE OF SPECIFIC WOODEN ARTICLES
- B27M3/00—Manufacture or reconditioning of specific semi-finished or finished articles
- B27M3/0013—Manufacture or reconditioning of specific semi-finished or finished articles of composite or compound articles
- B27M3/0086—Manufacture or reconditioning of specific semi-finished or finished articles of composite or compound articles characterised by connecting using glue
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16B—DEVICES FOR FASTENING OR SECURING CONSTRUCTIONAL ELEMENTS OR MACHINE PARTS TOGETHER, e.g. NAILS, BOLTS, CIRCLIPS, CLAMPS, CLIPS OR WEDGES; JOINTS OR JOINTING
- F16B12/00—Jointing of furniture or the like, e.g. hidden from exterior
- F16B12/04—Non-loosenable joints for non-metal furniture parts, e.g. glued
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16B—DEVICES FOR FASTENING OR SECURING CONSTRUCTIONAL ELEMENTS OR MACHINE PARTS TOGETHER, e.g. NAILS, BOLTS, CIRCLIPS, CLAMPS, CLIPS OR WEDGES; JOINTS OR JOINTING
- F16B12/00—Jointing of furniture or the like, e.g. hidden from exterior
- F16B12/04—Non-loosenable joints for non-metal furniture parts, e.g. glued
- F16B2012/043—Non-loosenable joints for non-metal furniture parts, e.g. glued using carpentry joints other than mortise and tenon joints, e.g. using multiple tenons
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T403/00—Joints and connections
- Y10T403/70—Interfitted members
- Y10T403/7045—Interdigitated ends
Definitions
- the present invention relates to the field of structural butt finger joints for flat boards, in which two flat boards are attached by their respective butts, by means of coupling together complementary coupling finger-, saw- or tooth-shaped configurations, and by means of adhesive, obtaining as a result a unitary, projection-free and structurally resistant element formed by the attachment of two flat boards.
- the finger profiles used in finger joints are conventionally generated in boards by means of routers with a rotary butt with the shape of the finger profile, the axis of rotation of the router being parallel to the main face of the board (the face having a larger surface).
- This solution makes it impossible to generate a finger profile that only covers a portion of the thickness of the board, because the butt of the router is circular and must go through the entire thickness of the board to generate said finger profile.
- Patent documents such as CN201856278, are also known in which boards attached by means of conventional structural finger joints are attached in a staggered manner, the assembling making it possible for the joints to be staggered.
- This solution does not provide a solution that allows forming a butt joint in two boards with a large contact surface and high structural resistance, because since the superposition of boards is required, the assembly is very thick, and since the attachment planes between boards with staggered joints coincide, the resistance thereof is also negatively affected.
- this patent document describe a method that allows producing two independent boards that can be transported separately and attached in situ by means of staggered and finger-shaped coupling configurations.
- Structural finger joints are also known in which the fingers are staggered with respect to one another to increase the contact surface, such as those disclosed by means of patent document WO2013044939. This staggering does not produce different finger profiles staggered with respect to one another and spaced by means of tread planes, but rather they are staggered laterally, the increase in contact surface therefore being limited.
- Patent documents describing methods and machines capable of milling boards by numerical control are also known, such as, for example, by means of patent documents CN103372897 and WO2008142684, but they do not describe their use for obtaining structural joints.
- a board is understood to be a rigid element made from a resistant and tenacious material suitable for structural use, and it can be homogenous, aggregate or laminar, such as, for example, wood, laminated wood, plywood, aggregate made from wood shavings, chips or powder or from fibers, resin-, plastic-, metal-based material, or other products having similar features.
- each of said first and second board has the butt thereof configured by a plurality of staggered steps, each step forming a tread plane parallel to the main faces of the board and a riser perpendicular to said main faces, in that at least one of said risers has a finger profile.
- the finger profile of each of the boards is made up of a plurality of risers having a finger profile perpendicular to the faces of the board having a larger surface, each with a height of only a fraction of the thickness of the board, and not being aligned but rather staggered, leaving a tread plane perpendicular to the risers exposed between each of said risers.
- This configuration allows, when attaching the first and second finger profiles, the contact surface between the two boards to increase, as the surfaces of all the staggered tread planes are added to the surface of the development of the finger profile.
- This increase in the surface results in a large surface for the glue, and allows distributing structural stresses over a larger surface, thereby reducing isolated stresses, and therefore creating a more resistant joint without increasing the section of the boards.
- This embodiment also allows the first and/or the last step to not have a finger profile, such that once the boards are attached, the visible joint will be a straight edge and not a finger profile, thereby better concealing said joint.
- all the risers of the mentioned staggered steps have a finger profile, which allows maximizing the contact surface between the two boards and assuring a resistant structural joint.
- the risers having a finger profile have a serrated profile, each finger being defined by two planes converging in an acute angle.
- the inclination of said acute angle is optimized to provide optimal structural resistance, distributing the forces to be transmitted between tensile and shear forces to be withstood by the glue or resin attaching both boards to one another.
- This angle the two faces of each finger form with one another is comprised between 10° and 15°.
- each finger The width and the thickness of each finger are adapted and different if the forces expected to be withstood by said finger are compressive and/or flexural compressive and/or tensile and/or flexural tensile forces.
- the forces that said joint must withstand can thereby be calculated beforehand, and the fingers can be designed such that they optimally withstand said expected forces.
- the fingers adapted for withstanding tensile and/or flexural tensile forces are wider and longer than the fingers adapted for withstanding compressive and/or flexural compressive forces, because it has been calculated that the resistance of the structural joint is maximized in this way.
- all the fingers form the same angle, regardless of size, because an optimal angle in which the glue attaching two facing fingers works optimally against tensile and shear forces that must be withstood in said angle has been calculated.
- the finger profiles used in the finger joints are conventionally generated in boards by means of routers with a rotary head having the shape of the finger profile, the axis of rotation of the router being parallel to the main face of the board.
- the proposed structural finger joint has, according to a preferred embodiment, staggered steps and finger profiles obtained by means of a rotary router capable of performing a staggered milling of successive portions of the thickness of the board, generating the tread planes parallel to the main faces of the board and the risers perpendicular to said main faces of the board, following a computer model of the finger profile, by means of the milling tool.
- staggered steps can be obtained by molding or by the staggered superposition and attachment of a plurality of laminas.
- the flat boards provided with the finger profiles serving as coupling configurations are produced, and said boards can be packaged, stored, and/or easily transported to a warehouse, distribution center, shop, or the like, or directly to the final site for the construction, assembly or mounting thereof.
- the first and second finger profiles, with their corresponding staggered steps are coupled to one another.
- the described method can also include obtaining the first and second finger profiles by means of a milling tool, said milling tool being a programmable machine tool provided with a rotary milling head, and performing the following steps:
- the coupling configuration could be achieved by means of a mold with a counter-shape of the staggered finger profile.
- references to geometric positions such as, for example, parallel, perpendicular, tangent, etc., allow for deviations of up to ⁇ 5° with respect to the theoretical position defined by said nomenclature.
- FIG. 1 shows an axonometric view of a first board provided with a finger profile at the butt thereof, configured in three steps and the size of the fingers in the top half being different from those in the bottom half of the mentioned first board, said first board facing and being spaced from a second board provided with a complementary finger profile;
- FIG. 2 shows an axonometric view of the first and second boards shown in FIG. 1 coupled to one another, both being aligned and flush, the fingers that are concealed within the structural joint being shown with a discontinuous line;
- FIG. 3 shows the same view as in FIG. 2 but without the discontinuous lines showing the concealed fingers.
- the present structural butt finger joint for flat boards consists of first and second flat boards 1 and 2 of wood, said boards 1 and 2 also being able to be made from other products derived from wood, such as laminated panels, conglomerate panels, etc.
- a flat board 1 or 2 has an approximately parallelepiped shape, having two main faces 10 having a larger surface parallel to one another, two butts of the board 1 or 2 at the ends thereof farthest from one another, and two sides 11 having the same length as the main faces 10 and a smaller surface than same.
- the proposed structural joint allows attaching said two boards 1 and 2 at their butts, achieving a resistant joint capable of correctly transmitting compressive, tensile, flexural forces or a combination thereof, from the first board 1 to the second board 2 or vice versa.
- each step 21 of the first board 1 forms a tread plane 22 parallel to the main faces 10 of the board, and a riser 23 perpendicular to said main faces 10 .
- each step 31 of the second board 2 forms a tread plane 32 parallel to the main faces 10 of the board and a riser 33 perpendicular to said main faces 10 .
- both boards 1 and 2 By recessing said steps 21 and 31 at the butt of both boards 1 and 2 in a complementary manner, the butts of both boards 1 and 2 can be overlapped, both boards 1 and 2 being flush, and having a large contact surface between both boards in the direction parallel to their main faces 10 , said contact surface being the sum of all their tread planes 22 or 32 .
- the first board 1 has a finger profile 20 that is complementary to a finger profile 30 provided in the riser planes 33 of the second board 2 , said contact surface in the direction that is perpendicular to that of the main faces 10 thereof being the sum of all the riser planes 23 or 33 .
- a structural joint is shown in which the staggering consists, in the first board 1 , of three steps 21 , providing two tread planes 22 and three riser planes 23 .
- the second board 2 consists of three steps 31 , providing two tread planes 32 and three riser planes 33 complementary to those of the first board 1 .
- the finger profile 20 and 30 consists of a plurality of fingers 24 and 34 , each of said fingers 24 and 34 being defined by two planes converging in an acute angle, with a rounded intersection.
- the inclination of said acute angle is optimized so as to provide optimal structural resistance, distributing the forces to be transmitted between tensile and shear forces to be withstood by the adhesive, glue or resin.
- This angle which the two faces of each finger form with one another is approximately 12° in this example, being able to be larger or smaller, depending on the type of adhesive used.
- This embodiment corresponds to the structural joint of first and second boards 1 and 2 intended for being used as beams.
- the beam will typically have one half subjected to traction and the other half subjected to compression, the half subjected to traction being able to be in the top or bottom half, depending on if the bending moments in that section of the beam are negative or positive.
- the proposed structural joint shown in the embodiment of FIG. 3 adapts the geometry of the finger profile 20 and 30 to the forces to be withstood provided for the section in which said structural joint is located. To that end, the width and length of each finger are changed, the fingers provided for withstanding tensile forces being smaller than the fingers provided for withstanding compressive forces. As a result, in the example illustrated in FIG. 1 fingers 24 and 34 in the bottom half of the first and second boards 1 and 2 are shown to have a smaller size than the fingers 24 and 34 in the top half of the first and second boards 1 and 2 .
- all the fingers 24 and 34 will be equal to one another.
- the fingers 24 , 34 of one step 21 , 31 could be different from the fingers 24 , 34 of the other steps 21 , 31 , or one or several of the steps 21 , 31 could be lacking fingers 24 , 34 , the riser plane 23 , 33 therefore being completely straight.
- each step 21 , 31 can be changed so that they are not all the same.
Abstract
Description
- The present invention relates to the field of structural butt finger joints for flat boards, in which two flat boards are attached by their respective butts, by means of coupling together complementary coupling finger-, saw- or tooth-shaped configurations, and by means of adhesive, obtaining as a result a unitary, projection-free and structurally resistant element formed by the attachment of two flat boards.
- Structural butt finger joint systems for flat boards are known.
- The finger profiles used in finger joints are conventionally generated in boards by means of routers with a rotary butt with the shape of the finger profile, the axis of rotation of the router being parallel to the main face of the board (the face having a larger surface). This solution makes it impossible to generate a finger profile that only covers a portion of the thickness of the board, because the butt of the router is circular and must go through the entire thickness of the board to generate said finger profile. Furthermore, to modify and adapt the finger profile to each board, it is necessary to replace the milling head.
- Nevertheless, some solutions are known, such as the solution disclosed in patent document DE841344, showing a board in which half the thickness thereof has been trimmed at an end portion, and where parallel grooves separating a plurality of fingers are made in the half that has not been trimmed. The combination of the grooves and the trimming causes half the extension of said fingers to extend such that they are completely separated from one another. Two complementary boards of this type can be coupled to one another by inserting the fingers of one board into the grooves of the other board. As can be seen, in this embodiment the end of the fingers is curved as is the bottom of the grooves, so there is no contact plane perpendicular to the main faces. This is due to the process of manufacturing by means of a router with an axis parallel to the largest main faces of the boards, and it causes the unwanted effect of causing a more hindered transmission of axial loads as two faces are not perpendicular to said opposing loads. That is because the solution described in this patent document is used to assemble non-structural cladding elements, and therefore the resistance requirements are not taken into account, whereas the need to conceal the joint has prevailed, showing a straight joint on one of its faces, for aesthetic purposes.
- Patent documents such as CN201856278, are also known in which boards attached by means of conventional structural finger joints are attached in a staggered manner, the assembling making it possible for the joints to be staggered. This solution does not provide a solution that allows forming a butt joint in two boards with a large contact surface and high structural resistance, because since the superposition of boards is required, the assembly is very thick, and since the attachment planes between boards with staggered joints coincide, the resistance thereof is also negatively affected. Nor does this patent document describe a method that allows producing two independent boards that can be transported separately and attached in situ by means of staggered and finger-shaped coupling configurations.
- Structural finger joints are also known in which the fingers are staggered with respect to one another to increase the contact surface, such as those disclosed by means of patent document WO2013044939. This staggering does not produce different finger profiles staggered with respect to one another and spaced by means of tread planes, but rather they are staggered laterally, the increase in contact surface therefore being limited.
- Furthermore, there are other patent documents describing different finger joint solutions with improved resistance capacities, such as, for example, those disclosed in patent documents U.S. Pat. No. 692,340 and US2007125448, but they use different operating principles and methods of manufacture.
- Patent documents describing methods and machines capable of milling boards by numerical control are also known, such as, for example, by means of patent documents CN103372897 and WO2008142684, but they do not describe their use for obtaining structural joints.
- The attachment of small-sized elements is often required in construction techniques, due to limitations of manufacture or transport, which elements must be attached for obtaining large-sized elements, such as, for example, construction elements, or furniture parts. This is particularly important is in the case of structural elements, in which continuity of the material is important for the purpose of achieving correct transmission of structural forces and loads to be withstood, preventing weak or easily fractured points. The techniques described above show certain deficiencies as regards the correct transmission of loads. The present invention solves the foregoing and other deficiencies by means of a structural butt finger joint for flat boards, comprising, in a manner that is already known through the prior art documents:
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- a first board, with two parallel main faces having a larger surface, two side faces and two butts, with a first finger profile formed by a plurality of fingers in at least one of the butts of said first board;
- a second board, with two parallel main faces having a larger surface, two side faces and two butts, with a second finger profile, complementary to the first finger profile formed by a plurality of fingers in at least one of the butts of said second board;
the first board and second board being coplanar, adjacent and attached by means of coupling and gluing the first finger profile with the second finger profile.
- A board is understood to be a rigid element made from a resistant and tenacious material suitable for structural use, and it can be homogenous, aggregate or laminar, such as, for example, wood, laminated wood, plywood, aggregate made from wood shavings, chips or powder or from fibers, resin-, plastic-, metal-based material, or other products having similar features.
- Easy-to-cut, lightweight and resistant materials, or other materials, such as wood or plastic derivatives, are preferred, although more resistant materials such as metals are also contemplated. Some of these materials can also be recycled and recyclable, so they are optimal materials for this use.
- The structural finger joint of the present invention differs from the known prior art and is characterized in that each of said first and second board has the butt thereof configured by a plurality of staggered steps, each step forming a tread plane parallel to the main faces of the board and a riser perpendicular to said main faces, in that at least one of said risers has a finger profile.
- In that sense, the finger profile of each of the boards is made up of a plurality of risers having a finger profile perpendicular to the faces of the board having a larger surface, each with a height of only a fraction of the thickness of the board, and not being aligned but rather staggered, leaving a tread plane perpendicular to the risers exposed between each of said risers.
- This configuration allows, when attaching the first and second finger profiles, the contact surface between the two boards to increase, as the surfaces of all the staggered tread planes are added to the surface of the development of the finger profile. This increase in the surface results in a large surface for the glue, and allows distributing structural stresses over a larger surface, thereby reducing isolated stresses, and therefore creating a more resistant joint without increasing the section of the boards.
- This embodiment also allows the first and/or the last step to not have a finger profile, such that once the boards are attached, the visible joint will be a straight edge and not a finger profile, thereby better concealing said joint.
- According to another embodiment, all the risers of the mentioned staggered steps have a finger profile, which allows maximizing the contact surface between the two boards and assuring a resistant structural joint.
- Optionally, the risers having a finger profile have a serrated profile, each finger being defined by two planes converging in an acute angle.
- The inclination of said acute angle is optimized to provide optimal structural resistance, distributing the forces to be transmitted between tensile and shear forces to be withstood by the glue or resin attaching both boards to one another. This angle the two faces of each finger form with one another is comprised between 10° and 15°.
- The width and the thickness of each finger are adapted and different if the forces expected to be withstood by said finger are compressive and/or flexural compressive and/or tensile and/or flexural tensile forces. The forces that said joint must withstand can thereby be calculated beforehand, and the fingers can be designed such that they optimally withstand said expected forces.
- Preferably, the fingers adapted for withstanding tensile and/or flexural tensile forces are wider and longer than the fingers adapted for withstanding compressive and/or flexural compressive forces, because it has been calculated that the resistance of the structural joint is maximized in this way.
- In another embodiment, all the fingers form the same angle, regardless of size, because an optimal angle in which the glue attaching two facing fingers works optimally against tensile and shear forces that must be withstood in said angle has been calculated.
- The finger profiles used in the finger joints are conventionally generated in boards by means of routers with a rotary head having the shape of the finger profile, the axis of rotation of the router being parallel to the main face of the board. This solution makes it impossible to generate a finger profile that only covers a portion of the thickness of the board, because the head of the router is circular and must go through the entire thickness of the board to generate said finger profile of straight walls. Furthermore, to modify and adapt the finger profile to each board, it is necessary to replace the milling head.
- As a result, the proposed structural finger joint has, according to a preferred embodiment, staggered steps and finger profiles obtained by means of a rotary router capable of performing a staggered milling of successive portions of the thickness of the board, generating the tread planes parallel to the main faces of the board and the risers perpendicular to said main faces of the board, following a computer model of the finger profile, by means of the milling tool.
- Furthermore, since the shape of the fingers is not conditioned by the shape of the milling head, but rather by the movement said milling head makes following the computer model that can be readily programmed, this solution allows being able to adapt the shape each finger joint to the needs of each board.
- Additionally, said staggered steps can be obtained by molding or by the staggered superposition and attachment of a plurality of laminas.
- By using the described structural finger joint, a new method can be used for the butt joint in flat boards. This method has the following steps:
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- obtaining a first board, with two parallel main faces having a larger surface, two side faces and two butts at the ends thereof farthest from one another, with a first finger profile formed in at least one of the butts thereof, configured by a plurality of staggered steps, each step forming a tread plane parallel to the main faces of the board and a riser perpendicular to said main faces, and where at least one of said risers has a finger profile;
- obtaining a second board, with two parallel main faces having a larger surface, two side faces and two butts at the ends thereof farthest from one another, with a second finger profile, complementary to the first finger profile, formed in at least one of the butts thereof, configured by a plurality of staggered steps, each step forming a tread plane parallel to the main faces of the board and a riser perpendicular to said main faces, and where at least one of said risers has a finger profile;
- transporting the first and second board to the construction and/or assembly site;
- attaching the first finger profile to the second finger profile by means of adhesive, glue or resin.
- So, first the flat boards provided with the finger profiles serving as coupling configurations are produced, and said boards can be packaged, stored, and/or easily transported to a warehouse, distribution center, shop, or the like, or directly to the final site for the construction, assembly or mounting thereof. Once the boards are at the construction and/or assembly site, the first and second finger profiles, with their corresponding staggered steps, are coupled to one another.
- The assembly of the boards in the construction and/or assembly site is possible as a result of the fact that the proposed structural joint solution provides a larger contact surface between the two boards with respect to previously known joints, which allows a larger surface for the glue, adhesive or resin, and this reduces demands on this attachment material, which allows being able to carry out the attachment in a less controlled environment than that of the manufacturing center, such as the construction and/or assembly site.
- Additionally, the described method can also include obtaining the first and second finger profiles by means of a milling tool, said milling tool being a programmable machine tool provided with a rotary milling head, and performing the following steps:
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- a) obtaining a computer model of the finger profile to be formed in each board, being each finger profile formed by a plurality of staggered steps, each step forming a tread plane parallel to the main faces of the board and a riser perpendicular to said main faces, and where at least one of said risers has a finger profile;
- b) performing a staggered milling of successive portions of the thickness of the board (1 or 2), generating the tread planes (22, 32) and the risers (23, 33), following the computer model of the finger profile, by means of the milling tool.
- Likewise, other techniques allow obtaining the proposed structural joint, for example in the case of using moldable materials, the coupling configuration could be achieved by means of a mold with a counter-shape of the staggered finger profile.
- It will be understood that references to geometric positions, such as, for example, parallel, perpendicular, tangent, etc., allow for deviations of up to ±5° with respect to the theoretical position defined by said nomenclature.
- Other features of the invention will be seen in the following detailed description of an embodiment.
- The foregoing and other advantages and features will be better understood from the following detailed description of an embodiment in reference to the attached drawings, which must be interpreted in an illustrative and non-limiting manner, in which:
-
FIG. 1 shows an axonometric view of a first board provided with a finger profile at the butt thereof, configured in three steps and the size of the fingers in the top half being different from those in the bottom half of the mentioned first board, said first board facing and being spaced from a second board provided with a complementary finger profile; -
FIG. 2 shows an axonometric view of the first and second boards shown inFIG. 1 coupled to one another, both being aligned and flush, the fingers that are concealed within the structural joint being shown with a discontinuous line; -
FIG. 3 shows the same view as inFIG. 2 but without the discontinuous lines showing the concealed fingers. - According to a non-limiting embodiment shown in
FIG. 1 , the present structural butt finger joint for flat boards consists of first and secondflat boards boards - It is understood that a
flat board main faces 10 having a larger surface parallel to one another, two butts of theboard sides 11 having the same length as the main faces 10 and a smaller surface than same. - The proposed structural joint allows attaching said two
boards first board 1 to thesecond board 2 or vice versa. - To form said structural joint, a series of staggered recesses are made in the area close to the butt of both
boards step 21 of thefirst board 1 forms atread plane 22 parallel to the main faces 10 of the board, and ariser 23 perpendicular to said main faces 10. Likewise, eachstep 31 of thesecond board 2 forms atread plane 32 parallel to the main faces 10 of the board and ariser 33 perpendicular to said main faces 10. - By recessing said
steps boards boards boards main faces 10, said contact surface being the sum of all theirtread planes - To also increase the contact surface between both
boards main faces 10, it is provided that in the riser planes 23 thefirst board 1 has afinger profile 20 that is complementary to afinger profile 30 provided in the riser planes 33 of thesecond board 2, said contact surface in the direction that is perpendicular to that of the main faces 10 thereof being the sum of all the riser planes 23 or 33. - By means of the combination of these two strategies, i.e., staggering and finger profiles, a large contact surface is generated between both
boards boards - In the embodiment shown in
FIG. 1 , a structural joint is shown in which the staggering consists, in thefirst board 1, of threesteps 21, providing twotread planes 22 and three riser planes 23. Likewise, thesecond board 2 consists of threesteps 31, providing twotread planes 32 and threeriser planes 33 complementary to those of thefirst board 1. - In this non-limiting example, the
finger profile fingers fingers - The inclination of said acute angle is optimized so as to provide optimal structural resistance, distributing the forces to be transmitted between tensile and shear forces to be withstood by the adhesive, glue or resin. This angle which the two faces of each finger form with one another is approximately 12° in this example, being able to be larger or smaller, depending on the type of adhesive used.
- This embodiment corresponds to the structural joint of first and
second boards - The proposed structural joint shown in the embodiment of
FIG. 3 adapts the geometry of thefinger profile FIG. 1 fingers second boards fingers second boards - In one embodiment in which different forces are not expected in different areas of the joint, all the
fingers - In alternative embodiments, the
fingers step fingers other steps steps fingers riser plane - Likewise, the height of each
step
Claims (19)
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
ES201431843A ES2574356B1 (en) | 2014-12-16 | 2014-12-16 | Structural joint to testero for flat boards, and method of construction |
ES201431843 | 2014-12-16 | ||
PCT/ES2015/070912 WO2016097449A1 (en) | 2014-12-16 | 2015-12-15 | Structural butt finger joint for flat boards |
Publications (2)
Publication Number | Publication Date |
---|---|
US20180229394A1 true US20180229394A1 (en) | 2018-08-16 |
US10543614B2 US10543614B2 (en) | 2020-01-28 |
Family
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Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US15/537,000 Expired - Fee Related US10543614B2 (en) | 2014-12-16 | 2015-12-15 | Structural butt finger joint for flat boards |
Country Status (5)
Country | Link |
---|---|
US (1) | US10543614B2 (en) |
EP (1) | EP3235613B1 (en) |
AR (1) | AR103049A1 (en) |
ES (1) | ES2574356B1 (en) |
WO (1) | WO2016097449A1 (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN115319870A (en) * | 2022-07-25 | 2022-11-11 | 广东顺德永强福泰智能木工机械有限公司 | Full-automatic wood board tooth joint integrated production line |
US20230167638A1 (en) * | 2020-06-05 | 2023-06-01 | Phylem Structures, S.L. | Engineered wood structural system |
Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CH266712A (en) * | 1948-07-03 | 1950-02-15 | Geiger & Cie | Wooden part made from pieces of wood glued together to withstand tension and bending. |
FR1180575A (en) * | 1957-08-05 | 1959-06-05 | Two or more piece broom handle | |
US3692340A (en) * | 1969-04-08 | 1972-09-19 | Ahti Aadolf Roth | Finger joint for jointing boards, battens, planks, and other comparable bodies |
US5313758A (en) * | 1988-12-16 | 1994-05-24 | Oy Partek Ab | Construction board and its manufacturing method |
WO2013044939A1 (en) * | 2011-09-27 | 2013-04-04 | 3B Structure Sprl | Splined joint for assembling components made of fibrous materials |
CN103378897A (en) * | 2012-04-23 | 2013-10-30 | 中兴通讯股份有限公司 | Device and method for achieving CMMB diversity reception |
CN103372897A (en) * | 2012-04-21 | 2013-10-30 | 上海卓畅数码科技有限公司 | Five-axis linked CNC (Computer Numerical Control) double-faced mill |
US20130316127A1 (en) * | 2011-02-28 | 2013-11-28 | Koyo Sangyo Co., Ltd. | Bamboo board and a composite board and fabrication method for same |
WO2014125358A1 (en) * | 2013-02-13 | 2014-08-21 | Stora Enso Oyj | Joint system and method for providing a joint system |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2753289A1 (en) * | 1977-11-30 | 1979-05-31 | Ernst Josef Meeth | Mitre cornered small pronged shank assembled window frame - has extensions at bottom of side pieces covering recesses in bottom shank ends |
US20020076275A1 (en) * | 2000-08-01 | 2002-06-20 | Roland Hernandez | Finger-joint in finger-jointed lumber |
US6537625B2 (en) * | 2000-08-01 | 2003-03-25 | The United States Of America As Represented By The Secretary Of Agriculture | Concentric finger jointed timber |
US20070125448A1 (en) * | 2005-12-06 | 2007-06-07 | Abbott Richard T | Assembly and method for providing an interlocking angular end joint |
AT9494U1 (en) * | 2006-11-02 | 2007-11-15 | Team 7 Natuerlich Wohnen Gmbh | WOODWORK, PARTICULARLY IN LEISTEN- OR BRETTFORM |
IL183364A (en) * | 2007-05-21 | 2010-03-28 | Rlbd Yazamut Iskit Ltd | Patterning plasterboard and plasterboard products |
CN201856278U (en) * | 2010-08-03 | 2011-06-08 | 中国林业科学研究院 | Dislocation finger joint recombined structural wood |
-
2014
- 2014-12-16 ES ES201431843A patent/ES2574356B1/en not_active Expired - Fee Related
-
2015
- 2015-12-15 EP EP15828817.5A patent/EP3235613B1/en not_active Not-in-force
- 2015-12-15 AR ARP150104107A patent/AR103049A1/en unknown
- 2015-12-15 WO PCT/ES2015/070912 patent/WO2016097449A1/en active Application Filing
- 2015-12-15 US US15/537,000 patent/US10543614B2/en not_active Expired - Fee Related
Patent Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CH266712A (en) * | 1948-07-03 | 1950-02-15 | Geiger & Cie | Wooden part made from pieces of wood glued together to withstand tension and bending. |
FR1180575A (en) * | 1957-08-05 | 1959-06-05 | Two or more piece broom handle | |
US3692340A (en) * | 1969-04-08 | 1972-09-19 | Ahti Aadolf Roth | Finger joint for jointing boards, battens, planks, and other comparable bodies |
US5313758A (en) * | 1988-12-16 | 1994-05-24 | Oy Partek Ab | Construction board and its manufacturing method |
US20130316127A1 (en) * | 2011-02-28 | 2013-11-28 | Koyo Sangyo Co., Ltd. | Bamboo board and a composite board and fabrication method for same |
WO2013044939A1 (en) * | 2011-09-27 | 2013-04-04 | 3B Structure Sprl | Splined joint for assembling components made of fibrous materials |
CN103372897A (en) * | 2012-04-21 | 2013-10-30 | 上海卓畅数码科技有限公司 | Five-axis linked CNC (Computer Numerical Control) double-faced mill |
CN103378897A (en) * | 2012-04-23 | 2013-10-30 | 中兴通讯股份有限公司 | Device and method for achieving CMMB diversity reception |
WO2014125358A1 (en) * | 2013-02-13 | 2014-08-21 | Stora Enso Oyj | Joint system and method for providing a joint system |
Non-Patent Citations (1)
Title |
---|
AT-9494-U1 * |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20230167638A1 (en) * | 2020-06-05 | 2023-06-01 | Phylem Structures, S.L. | Engineered wood structural system |
US11846100B2 (en) * | 2020-06-05 | 2023-12-19 | Phylem Structures, S.L. | Engineered wood structural system |
CN115319870A (en) * | 2022-07-25 | 2022-11-11 | 广东顺德永强福泰智能木工机械有限公司 | Full-automatic wood board tooth joint integrated production line |
Also Published As
Publication number | Publication date |
---|---|
EP3235613B1 (en) | 2018-12-05 |
EP3235613A1 (en) | 2017-10-25 |
WO2016097449A1 (en) | 2016-06-23 |
ES2574356A1 (en) | 2016-06-16 |
AR103049A1 (en) | 2017-04-12 |
US10543614B2 (en) | 2020-01-28 |
ES2574356B1 (en) | 2017-05-05 |
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